The present invention is directed to an arrangement or device for controlling the transfer and orientation of batchwise arranged flat objects, such as blanks cut from a solid or corrugated board and piled on one another. The device includes a transfer and orientation plane including a tray with driven carrier balls, and the tray is equipped with a lifting device.
In the field of handling stacked or unstacked plate-like material, devices for orientating and carrying such objects are already known.
U.S. Pat. No. 3,828,917 discloses a device which includes a fixed table equipped with carrier balls. Each of these balls is individually driven by a friction drive unit including a disk mounted on a shaft having a pulley which pulley is driven or rotated by toothed belts. The units consisting of the disk and pulley are permanently assembled on a base plate which can be shifted lengthwise and crosswise by means of two jacks or a piston and cylinder arrangement relative to the fixed table. Such a shifting involving the base plate with regard to the fixed table can cause a variation in the speed of rotation of the carrier balls or also a change in their direction of rotation. These changes will allow an orientation of a pile of objects in a desired direction. An appropriate movement of the base plate will allow a pivoting of a pile of objects around its own axis.
U.S. Pat. No. 3,442,410 discloses another device for orientating a batch of objects. The device of this patent includes an assembly which has several endless belt conveyors between which is fitted a cross-shaped table which is mounted on a shaft which can be rotated in alternating directions, as controlled by two pneumatic pistons. Moreover, this table is fitted in a cradle which is connected to two pneumatic pistons arranged to shift it in a vertical direction so that the table can lift an object above the plane of the endless belt conveyors. Thus, by shifting the table in the vertical direction and also rotating it on its shaft, the orientation of an object can be changed prior to be continuously conveyed on the belts of the device.
A third device for orientating pilewise or batchwise arranged objects is disclosed in U.S. Pat. No. 2,897,948, which is similar to the above-mentioned devices. In particular, this device includes a conveyor arrangement of conveying rollers positioned between two conveying belts. A table having apertures for receiving the rollers is mounted for both rotation and for lifting between a lower position with the rollers extending through the apertures of the table to an upper position with the table positioned above the rollers. In this particular arrangement, the table is rotated in a single direction, with the rotation being intermittent and through a 90.degree. angle. The raising of the table is obtained by a lever acting on a disk connected to a support shaft for the table.
Each of the above-mentioned devices, however, has certain drawbacks. For example, in the device of the first-mentioned patent, U.S. Pat. No. 3,828,917, the rotary ball motion requires a relatively complicated arrangement for each ball which is expected to be controlled. Moreover, the translation of the base plate relative to the table requires a separate control which is equally expensive to make. Besides that, the device does not allow for the disengagement of the balls from the load, which is represented by the weight of the object to be carried or reorientated, and the space between the various balls should be rather large, which design, as it might happen with the processing of relatively delicate materials, involves a considerable local load on the contact points between the balls and the lowermost sheet of the pile.
The device, which is disclosed by U.S. Pat. No. 3,442,410, is not provided with balls, but with belts for creating the conveyance of the objects and the inversion of the batches of such objects can only be achieved if the cross-shaped table occupies its upper position with regard to the plane represented by the endless belts of the conveyor In this execution and with regard to the cross-shaped table, there occurs a rotary movement, either backwards or forwards, accomplished jointly with the alternating vertical movement of the cross-shaped table. Both movements are created by pneumatic or hydraulic jacks. The design of this assembly requires the use of important means with a view to obtain a simple inversion of the object. Moreover, this device allows only one inversion of the object. There is no possibility to orient and, therefore, to direct the object toward different trajectories as this might be feasible with the first device, which was described hereinabove.
The third device of U.S. Pat. No. 2,897,948 has a design similar to that of the second device. In fact, it differs only by the configuration of the inverting table, which is actually rectangular and has apertures enabling the passage of an upper portion or part of each of the conveyor rollers when the table is in its lower position. In this execution, which also enables the rotation of the batches of objects only when the table is in its upper position, the rotary table drive has not been conceived in such a way as to impart an alternating movement, but rather only imparts an actual sequential movement, always in the same direction of rotation by means of a motor, whose electrical controls include a rod fitted to the table axis. The vertical movement is controlled by means of a device which includes a lever operated by a jack.
The shortcomings of these devices are the same as those already referred to in connection with the earlier-described devices.